A stator of an inner-rotor motor typically includes an annular yoke portion, a plurality of stator teeth extending from the yoke portion, and stator windings wound on the stator teeth. To improve heat dissipation, a plurality of axial projections is formed on the outside of the yoke portion, to increase the surface area of the stator exposed to the air. However, the projections usually have only a small axial length. An existing solution that further improves heat dissipation and maintains substantially same cost involves mounting metal fins on the outside of the stator wall. However, as the power of electrical appliances continues to increase, existing solutions for dissipating heat do not meet the requirements.
Thus there is a need for an electric motor having a stator with improved heat dissipation.